1. Field of the Invention
The present invention relates to toothbrushes, and more particularly, to toothbrushes which exhibit a three-dimensional bristle profile to provide improved cleaning in interproximal areas without increasing gum irritation.
2. Description of the Prior Art
The fundamental purpose of toothbrushes is to remove plaque and debris from tooth surfaces, both along their outer surfaces and in the interproximal areas. Most commercially available toothbrushes clean the outer surfaces of teeth adequately. However, applicants have discovered that a substantial improvement in toothbrush performance may be realized by optimizing toothbrush design for interproximal cleaning without sacrificing cleaning on the facial, lingual, buccal, and occlusal surfaces and without increasing gum irritation which often accompanies any attempt to improve interproximal cleaning. In particular, the present invention comprises an improved toothbrush having a "V" shaped pattern when viewed in side profile in combination with several other important operating characteristics which, when concurrently met, will render the toothbrush particularly adept at accomplishing the aforementioned objectives.
Toothbrushes having a "V" shaped side profile are generally known to those skilled in the art. However, it is believed that these known prior art toothbrushes do not exhibit all of the operating characteristics identified hereinafter as important to achieving improved interproximal cleaning without increasing gum irritation. For example, most of these prior "V" shaped toothbrushes lack bristles which are properly end rounded. This is due to the fact that the three-dimensional bristle pattern on such known brushes is often formed by cutting the exposed ends of the bristles to the desired configuration after the tufts have been stapled to the brush head. This leaves bristle tips having sharp chisel pointed edges which are difficult to end round due to their three-dimensional configuration, particularly in the valleys. Although such brushes will provide improved interproximal cleaning, without properly end rounded bristles these toothbrushes will irritate the user's gums, oftentimes leading the user to abandon use of the brush. Clearly, the improved interproximal cleaning benefit will not be realized if people refuse to use the toothbrush. Consequently, it is important that the exposed ends of the bristles be properly end rounded to avoid unnecessarily irritating the user's gums.
In addition to proper end rounding of the exposed bristle tips, other important operating characteristics have been identified in "V" shaped toothbrushes of the present invention to achieve improved interproximal cleaning. In particular, the shape and size of the "V" and the overall stiffness of the bristles are important characteristics which must be optimized in accordance with the disclosure set forth in the present specification to provide all of the benefits of the present invention.